Extreme Marathons

Each year, 4,000 competitors test themselves on an 81.3-mile course across six Alpine valleys, with 16,400 feet of elevation gain in 41 miles of climbing, reaching a maximum height of almost 9200 feet.
Olivier Maire / Keystone

Grand Raid Cristalp, Verbier, Switzerland
Each year, 4,000 competitors test themselves on an 81.3-mile course across six Alpine valleys, with 16,400 feet of elevation gain in 41 miles of climbing, reaching a maximum height of almost 9,200 feet.

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